A reduced model of the arterial tree

The arterial tree may be considered as a black box system, with the flow and pressure that are strongly pulsatile at input and nearly constant at output. Clinicians need a simple and realistic model of the arterial tree which enables explanation of age and disease related changes of the arterial tree. The physiological changes of the arterial tree should result in physiological changes of model parameters. The goal of this paper is to define a new lumped mathematical model of the arterial tree and compare it with Westerhof’s three element windkessel model (3WK), as one of the most frequently used model. The new proposed model is derived by reduction of the distributed model, and it consists of two viscoelastic chambers connected by a lossless tube and it contains six parameters. The proposed and 3WK models were applied to three typical human subjects: 28, 52 and 68 years old. The models are compared in terms of their ability to mimic changes of the arterial input impedance with physiological changes of the model parameters. The proposed model shows better ability to explain the effect of the arterial tree ageing, than the 3WK model, since its each parameter has a clear physiological meaning.